This invention relates generally to the field of catch basin filters used in conjunction with storm drains, such as are typically utilized with paved roads or parking lots to provide passage for rain water into a sewer or storm water underground conduit system, wherein the catch basin filters preclude debris, contaminants or hazardous waster from entering the underground conduit system.
Storm water systems usually comprise a plurality of grated storm drains set into a paved surface or along a curb, the drains allowing water from storm events to pass into an underground conduit system. The storm drains typically comprise catch basins—generally rectangular sumps having an outlet port opening into the removal conduits, the outlet port being raised a short distance above the sump bottom such that debris will be retained in the sump area. In many circumstances it is desirable or required that catch basin filters be utilized with the catch basins, the filters trapping debris, particulates, contaminants, hazardous waste, etc. before they enter the sump area. The filters are cleaned or replaced periodically or as needed.
One known type of catch basin filter comprises a horizontally disposed sheet-like filtering material, often formed with a depending sack-like member, which is placed on top of, envelopes, is attached to and/or is suspended from the apertured grate of the storm drain. Examples of this type of filter are shown in U.S. Pat. Nos. 5,372,714 and 5,575,925 to Logue, Jr. Another type of storm water filter uses a basket-like member that retains various filtering media, the basket-like member being suspended beneath the storm grate or mounted to the walls of the catch basin. An example of this type of filter is shown in U.S. Pat. No. 5,820,762 to Bamer et al. The disclosure of each of these patents is incorporated herein by reference.
In some instances it is desirable or required to take periodic or event-responsive samples of the storm water that has passed through the catch basin filter to insure that undesirable elements are not passing into the storm water conduit system. One way to accomplish this is to remove the storm grate and the catch basin filter to allow unencumbered access into the catch basin sump area for removal of a liquid sample. This technique is labor-intensive and time-consuming. Furthermore, sampling the water that is resident in the sump will not necessarily provide a true indication as to the continued effectiveness of the catch basin filter media or of the quality of the water passing through the filter, since the sump area can become contaminated and never purified, such that any sample taken will produce a negative result.
The '762 Bamer et al. patent shows a storm water catch basin filter that attempts to address this problem, but utilizes a relatively complex multi-valve and suction system to capture water flowing through the filter. Unfortunately however, this design suffers from the same drawback as the sump sampling method since a permanent cup is used to trap the sample, and this cup may become contaminated over time, thus giving false readings when samples are taken.
It is an object of this invention to provide a storm water catch basin filter that effectively addresses the problems outlined above by providing a sampling port for real-time sampling of storm water that has flowed through the filter, wherein the sampling port is easily accessible at any time.